Concentrator for solar energy generation and production thereof from polymeric materials

Abstract

The present invention relates to a concentrator for concentrating solar radiation and to the production thereof from polymeric materials. The concentrator according to the invention can be used in photovoltaically or in particular in solar thermally usable systems. The concentrator according to the invention allows for the efficient concentration of solar radiation onto objects such as solar cells, independent of the geometry thereof. This relates, for example, to the surface of a solar cell as it is used in concentrating photovoltaics, and also an absorber tube as it is used in concentrating solar heating, for example in the scope of the parabolic trough technology.

1 . A process for producing a concentrator, the process comprising:
 (a) coating a first side of a first polymer layer with a a metal mirror layer structure comprising a metal mirror layer by physical vapour deposition;   (b) applying a second polymer layer on on an opposite side of the metal mirror layer structure, to obtain a laminate; and   (c) cold curving the laminate, to obtain a self-supporting concentrator,   wherein one of the two polymer layers is highly transparent and faces a solar light source and the other is a backing layer and faces away from the solar light source.   
     
     
         2 . The process of  claim 1 , wherein, prior to (a), the first side of the first polymer layer comprises a highly transparent primer layer. 
     
     
         3 . The process of  claim 1 , wherein a side of the metal mirror layer in the metal mirror structure facing away from the highly transparent polymer layer comprises a metallic protective layer. 
     
     
         4 . The process of  claim 1 , comprising:
 coating the backing polymer layer with the metal mirror layer by physical vapour deposition; and then,   optionally, coating an opposite side of the metal mirror layer with a primer and a highly transparent polymer.   
     
     
         5 . The process of  claim 1 , wherein metal mirror layer structure comprises a reflection enhancement stack layer. 
     
     
         6 . The process of  claim 1 , wherein wherein the metal of the mirror layer is silver, gold, or aluminium, and the metal mirror layer has a thickness in a range from 50 to 200 nm. 
     
     
         7 . The process of  claim 6 , the silver mirror layer structure comprises:
 optionally a primer layer;   the metal mirror layer; and   optionally an anticorrosion layer obtained by physical vapour deposition.   
     
     
         8 . The process of  claim 1 , the highly transparent polymer is polycarbonate, polystyrene, a styrene copolymer, a fluoropolymer, or PMMA. 
     
     
         9 . The process of  claim 8 , the highly transparent layer comprises at least one additive selected from the group consisting of an inhibitor and a UV stabilizer. 
     
     
         10 . The process of  claim 8 , the highly transparent polymer layer is a multilayer of polymer layers and
 wherein the at least one additive is is homogenously present in the layers of the multilayer, present separately from one another between one or more the layers in the multilayer, or a combination thereof.   
     
     
         11 . The process of  claim 10 , wherein a polymer layer of the multilayer is a PMMA-comprising layer. 
     
     
         12 . The process of  claim 1 , the highly transparent layer comprises at least one selected from the group consisting of a scratch-resistant coating and an antisoil coating. 
     
     
         13 . The process of  claim 1 , wherein the polymer of the backing layer is polycarbonate, polystyrene, a styrene copolymer, a polyester, or PMMA. 
     
     
         14 . The process of  claim 1 , wherein adhesive layers are optionally present between each layer of the laminate. 
     
     
         15 . The process of  claim 1 , self-supporting, and may be simultaneously converted to the final form by cold shaping. 
     
     
         16 . The process of  claim 1 , wherein the concentrator has a total thickness in a range from 1 mm to 2 cm. 
     
     
         17 . A concentrator, comprising, viewed from a light source:
 a polymer layer comprising UV stabilizer, an inhibitor inhibitors, and PMMA;   a silver mirror layer structure having a thickness in a range from 80 and 200 nm;   a backing layer;   wherein a final form of the concentrator is obtained by cold forming.   
     
     
         18 . The concentrator of  claim 17 , further comprising a surface finish layer having a soil-repellent and a scratch resistance-improving property, and an optional first and second adhesive layer,
 wherein the concentrator has a structure comprising, viewed from the light source:   (i) the surface finish layer;   (ii) the polymer layer,   (iii) the optional first adhesive layer,   (iv) the silver mirror layer structure comprising
 (a) a primer layer, 
 (b) a silver layer having a thickness in a range from 80 and 130 nm, and 
 (c) an anticorrosion layer comprising copper or nickel-chromium and having a thickness in a range from 25 and 50 nm; 
   (v) the optional second adhesive layer; and   (vi) the polymeric backing layer, wherein the polymeric backing layer comprises PMMA, and   wherein a final form of the concentrator is obtained by cold forming.   
     
     
         19 . The concentrator of  claim 17 , in the form of a parabolic trough in a parabolic trough collector. 
     
     
         20 . The concentrator of  claim 17 , in the form of a Fresnel mirror collector, a heliostat reflector, or a solar dish concentrator unit. 
     
     
         21 .  17  or  18  in A solar thermal energy unit, comprising the concentrator of  claim 17 ,
 wherein the concentrator is in a curved form and the thermal energy unit is medium-scale or small-scale. 
 
     
     
         22 . A concentrated photovoltaic, comprising the concentrator of  claim 17 , wherein the concentrator is in paraboloid form.